So chasing a hard start, wost when the truck has to crank for a bit (real cold) or after sitting, cooled down for 1/2 hour or more.

Found the lift pump was blipping on when the key went to "ON". As it should, but no pressure while cranking. Seemed to help a bit, bumping the key to run the lift pump, then starting the truck.

Now (quick/easy) Ive got a switch on the dash, run to the "excite" position on the lift pump relay.

Starting order now goes:
turn key to ON
flip switch to run lift pump (when I think Im close to the start light going out)
Start truck, which now starts much easier, all the time
flip switch off.

Worst case, forget to turn the switch off, turn off the truck, and turn off the lift pump when I hear it still running. My guess, is this will help lift of the VP. FWIW, the lift pump relay is factory wired for the lift pump stuck into the tank.

 

I don't understand the switch for the lift pump. It should be wired to a trigger switch that is automatic for it to turn on and run for 45 seconds every time you turn the ignition on. Sounds to me like the LP is going bad. These in tank pumps are the wost case scenario for reliability. If your gonna chip that truck that pump has to go first or new VP will be your next problem.

 

Yer truck came new with a lift pump mounted on the drivers side of the motor, dealers started installing an intank pump sometime in 04-05 IIRC IF trucks came in with bad lift pumps , I had the golden opertunity to install a FassII for a friend of mine on his 99 so I made an article on it, along with this I also recommend Airdog as a good option


https://www.dieselbombers.com/5-9l-2...dont-walk.html

 

Here is a little video about testing the cranking pressure...

 

How much fuel pressure do you have when cranking?

 

Now have 10-12 when craniking, and 10-12 when driving as well.

Still working out great with this BTW.

And no, lift pump only runs for a second when you hit "ON' Pump runs for 30 seconds if you bump the starter.

vpp 44 is fairly new, lift pump is new, with the big straw in the tank dealy. Pump is a carter, and already killed 2 holley blacks. Truck had the aftermarket/factory in tank when I bought it, it was bad then, took out the vp in 15k miles, yay!

Truck is chipped, but pump wire is not tapped, yet.

 

Well hell... I know whats happening...





Carter pump are really common for spining the plastic hub inside the rotor. The plastic piece is not suppose to turn inside the rotor nor is it suppose to fall out. The other propblem you can't see with a Carter is the regulator. Is a check valve style BB that virbrates against the seat of the pump till it beats the seat so bad it no longer seals. Then there little to zero pressure. I've been through 5 Carter pumps and finally got smart and got a AirDog 150. But I've seen Carters fail in less than 1 MONTH!...

So do youself a favor and ditch the junk pump and upgrade to something better...

 

yep, same here, burnt through 3 carters in a month, wasted enough money so i bought a fass, at least get you the direct replacement pump from fass, there only 250-275 bucks new.